title: Immunological comparison of rat, rabbit, and human microsomal cytochromes P-450.
abstract: Antibodies were raised in rabbits to electrophoretically homogeneous cytochromes P-450 isolated from rat and human liver microsomes. These antibodies were used to compare various forms of rat, rabbit, and human cytochromes P-450 present in microsomes and in purified preparations by using double-diffusion analysis, immunoelectrophoresis, quantitative microcomplement fixation, competitive radioimmune assay and inhibition of enzyme activity toward d-benzphetamine and benzo[a]pyrene. The results indicate that (1) at least some forms of cytochrome P-450 from the three species share certain common immunological determinants, (2) there are immunological differences between cytochromes P-450 isolated from the three species, (3) some immunological differences exist between cytochromes P-450 isolated from rats of different strains, (4) immunologically distinguishable forms of cytochrome P-450 exist within individual human liver samples, and (5) human liver samples obtained from different individuals contain immunologically different forms of cytochrome P-450. Quantitative microcomplement fixation techniques were used to assign immunological distances to different form of rat, rabbit, and human liver microsomal cytochrome P-450. Cross-reactivity was observed in all systems tested, and the extent of immunological similarity was dependent upon the particular assay used.
mesh_terms: D000818:Animals; D003577:Cytochrome P-450 Enzyme System / Q000276:immunology / Q000302:isolation & purification; D005260:Female; D006801:Humans; D007106:Immune Sera; D007118:Immunoassay; D005779:Immunodiffusion; D008297:Male; D008862:Microsomes, Liver / Q000378:metabolism*; D011817:Rabbits; D011863:Radioimmunoassay; D051381:Rats; D013045:Species Specificity
chemical_list: D007106:Immune Sera; D003577:Cytochrome P-450 Enzyme System